Method and apparatus for forming ship hulls

ABSTRACT

D R A W I N G A METHOD OF AND APPARATUS FOR FABRICATING SECTIONS OF A VESSEL, THE METHOD COMPRISES PROVIDING SINGLY REINFORMED PLATE STRUCTURES AND BENDING THEN TO DESIRED FORM, AND THEREAFTER (1) JOINING TOGETHER SUCH BENT PLATE STRUCTURES, OPTIONALLY WITH INTERVENING UNBENT REINFORCED PLATE STRUCTURES, TO FORM A SHELL, AND THEREAFTER ERECTING TRUSSING WITHIN THE SHELL TO REINFORCE THE SAME, OR (2) FABRICATING A TRUSSED UNIT, AND WELDING THE BEND PLATE STRUCTURES TO THE TRUSSED UNIT, WITH OR WITHOUT INTERVENING UNBENT REINFORCED PLATE STRUCTURES, AND WELDING THE PLATE STRUCTURES TO ONE ANOTHER. THE APPARATUS COMPRISES A STATIONARY BED AND ONE OR MORE SWING FRAMES WHICH ARE MOUNTED SO THAT THEY CAN BE RAISED FROM LOWERED POSITIONS TO ERECT POSITIONS OT BEND A SINGLY REINFORCED PLATE ABOUT ONE OR MORE MANDRELS WHICH ARE SUPPORTED IN HOLD-DOWN RELATION TO A PART OF THE PLATE STRUCTURE.

. March 9, `1,971 A. H. zlDELL 3,568,300

' 5 METHOD AND- APPARATUS FOR FRMING SHIP HULLS A Filed July 2,1963 4 sheets-sheet 1 FIGLI. 33- 43 39 4oA 37 103m."

fs l FIG? +7 Iliff i 1 .'w BM l i. i i f//FG INVENTOR BUCKHORN, BLORE, KLARQUIST 8. SPARKMAN 'ATTORNE YS l IM"IHOD AND APPARATUS FOR FORMING SHIP I'IIULLS Filed JulyV 2'. 1968 4 Sheets-Sheet z .65? y Flein FIG.

ARNOLD H. AZ|DELL BY u lNvENToR BUCKHORN, BLORE, KLARQUIST 8. SPARKMAN ATTORNEYS Mmh .9,- 1971 3,568,300

METHOD AND APP'RATUS FOR FORMINGl SHIP HULLS A. HY. vzlDELl.

Filed. July a, 196s 4 ShdGtS-Sheet 5 I w .my

FIG. ls

FIG. l5

ARNOLD H. 21m-:LL INVENTOR BUCKHORN, BLORE, KLARQUIST & SPARKMAN FlG. 3@ 53N i lATTORNEYS Mardi 9, 1971 v A H, zlDELL 3,568,300

MEIHOD AND APPARATUS FOR FoRMNG SHIP HULLS Filed July 2. 1.968 4 sheets-sheet la W fr .BY

BUCKHORN, BLORE, KLRQUIST vSPA'RKMAN f ATTORNEYS United States Patent O 3,568,300 METHOD AND APPARATUS FOR FORMING SHIP HULLS Arnold H. Zidell, Portland, Oreg., assgnor to Zidell Explorations, Inc., Portland, Oreg. Filed July 2, 1968, Ser. No. 742,070 Int. Cl. B23k 31/02 U.S. Cl. 29-471.1 6 Claims ABSTRACT OF THE DISCLOSURE A method of and apparatus for fabricating sections of a vessel. The method comprises providing singly reinforced plate structures and bending them to desired form, and thereafter (l) joining together such bent plate structures, optionally with intervening unbent reinforced plate structures, to form a shell, and thereafter erecting trussing within the shell to reinforce the same, or (2) fabricating a trussed unit, and welding the lbent plate structures to the trussed unit, with or without intervening unbent reinforced plate structures, and welding the plate structures to one another.

The apparatus comprises a stationary bed and one or more swing frames which are mounted so that they can be raised from lowered positions to erect positions to bend a singly reinforced plate about one or more mandrels which are supported in hold-down relation to a part of the plate structure.

BODY OF THE APPLICATION A method now commonly employed of forming barge hull sections comprises providing two side plates, a deck plate and a bottom plate and welding these parts together. It is evident that seam welds must be provided, exclusive of the welding required on the trussing provided within the hull sections. ySince welding operations are time-consuming and expensive, they should be eliminated where possible.

The main object of the present invention is to provide an apparatus for and a method of forming a hull section that requires less seam welding than heretofore required.

In summary, my invention comprises a met-iod and apparatus described in the abstract.

Reference is made to the accompanying drawings, wherein:

FIG. 1 is a diagrammatic side elevational View of a jig on which rests a steel plate structure to be bent into a hull subsection;

FIG. 2 is a view of the same apparatus with the lefthand swing frame being elevated to `bend the left-hand portion of the plate structure;

FIG. 3 is like FIG. 2, but showing the left-hand swing frame in its erect position, having bent the left-hand portion of the plate structure at right angles to the central portion, and further showing the right-hand swing frame being elevated to bend the right-hand portion of the plate structure;

FIG. 4 is a view of the two swing frames in their erected positions with certain beams and tie members welded to the bent plate structure;

FIG. 4A is a diagrammatic bottom view of the bed of the apparatus taken in the direction of the arrows 4A-4A of FIG. 4 but on a scale smaller than that of FIG. 4;

FIG. 5 shows the hull subsection of FIG. 4 in its proper relationship to another subsection, similarly formed;

FIG. 6 is a view showing the two subsections welded together to form a hull section;

'ice

FIG. 7 is a side elevational view of the hull section;

IFIG. 8 is a view on a smaller scale than FIG. 7 of a typical barge hull showing in solid lines where the hull section of FIG. 6 might be employed;

IFIG. 9 is a fragmentary side elevational View of the jig disclosed in PIG. 1, with the plate structure to be bent resting on the jig, FIG. 9 being on a larger scale than FIG. 1 to more clearly show the details of construction of the jig;

IFIG. l0 is a view of the swing frames in their upright positions and showing the bent plate structure with buckframing and reinforcement in place;

FIG. r11 is an end elevational View taken in the direction of the arrows 111-11 of IFIG. 10;

FIG. 12 is a view like FIG. 6, but on a larger scale and showing more details of construction;

fFIG. 13 is an enlarged fragmentary view of the lower right-hand portion of FIG. 11, FIG. 13 being on a larger scale than IFIG. 11;

IFIG. 14 is a fragmentary vertical sectional View taken in the direction of the arrows 14-14 of FIG. 13; with parts broken away for convenience in illustration;

lFIG. l5 is a vertical fragmentary section taken along line 15-15 of FIG. 14;

FIG. 16 is a vertical fragmentary section taken along line 16-16 of FIG. 13;

FIG. 17 is a progressive view showing several stages of the bending step;

IFIG. 18 is a view of a modilied procedure for forming a hull section;

FIG. 19 is a diagrammatic view showing a furtherl modified form of procedure for forming a hull section;

FIG. 20 is a fragmentary side elevational view of a modified apparatus for bending double-direction reinforced plate;

PIG. 21 is a View like FIG. 20 but with the swing frames elevated and` with reinforcement in place;

GENERAL DESCRIPTION FIG. 1 shows that the jig apparatus includes a base frame 31 having a central platform 33 projecting upwardly from the base frame. A pair of swing frames 35 and 37 are pivoted on the base frame by pivot shafts 38. These swing frames in their lowered positions, as shown in fFIG. 1, form extensions of the platform 33 for supporting a workpiece. The workpiece is shown in the form of a singly reinforced rectangular plate structure 39. By singly reinforced it is meant reinforced in one direction, in this case, by angle pieces 40 extending transversely of the plate. The central portion of the plate structure 39 is held down against the central platform 33 by a pair of mandrels 41 and 43, which are mounted in place by clamps 45 and 47 in a manner to be presently described.

To bend the plate structure 33 about the mandrels 411 and 47, the swing frames are raised, such as by means of a crane, one swing frame, for instance, 35 being raised first to its erect position and then the other swing frame 37 being raised to its erect position. Thereafter, various reinforcements in the form of buokframing and trussing 49 is tack Welded in place to form a hull ha1f-sec tion S-1. The half-section S-1 is then removed from the apparatus and the welding job completed. It may be more desirable to tack-weld temporary holding elements or pieces in place instead of the trussing, and then remove the temporarily reinforced bent half-section and deposit it elsewhere for installation of the buckframing and trussing as a production job. Whether the reinforcement is by means of final trussing to be used in the vessel, or temporary holding pieces, these elements serve to hold the bent reinforced plates in the desired configuration.

FIG. 5 shows that the hull half-section S-l has been turned sideways from its FIG. 4 position, and arranged in facing relation to a second hull half-section C-2, which is formed in a manner similar to that used to form half-section S-1. The half-sections are welded together by seam welds at W-1 and W-'Z to provide a barge section S of the barge B in \FIG. 8.

DETAILED DESCRIPTION Referring to FIG. 4A, the individual beams making up the base frame 31 are numbered 31a-31e to aid in relating \FIG. 4 to the other figures, such as FIGS. 9 through 1l and 13 through 16. It is evident from FIG. l1 that the individual beams of the base frame 3'1, in the particular form of the invention shown, comprise H beams, and it is further evident that there are three longitudinally extending beams 31a, 31b and 311e and two end beams 31d and 31e.

'I'he central platform l33 actually comprises four plates, 33a, 33h, 33b and 33e, one for each of the beams 31a and 31o and two for beam 31b. The plates 63a and 33C are welded to the outer anges of the beams 31c and 31a (iFIG. l1) and plates 33h and 33b are welded to the flanges of central beam 31b.

Each of the swing frames 35 and 37 is of similar construction, and therefore only frame 3S will be described in complete detail. The swing frame is of open rectangular form, as is evident from FIG. 1.1, and is shown as comprising three longitudinal beams 35a, b and c of T-shape cross section (see FIG. 16) which are connected by transverse members 35d, e and f, there being diagonal reinforcement 35g and h.

The pivotal mounting of the swing frame to the base frame 31 is best shown in FIGS. 11 and 13 through 16. Since each of the longitudinal members 35a, b and c are pivotally connected in the same manner, the pivotal connection for member 35a only will be described. As shown in IFIG. 13, the flanges of member 35a are cut away at 50, the lower portion thereof, as the parts are shown in FIG. 13, to leave a narrow neck section 35a' which ts down between a pair of slot plates 51 and `53. The plates are welded to a common base element 55, which in turn is welded to the web of the associated beam 31a of the base frame. The associated pivot shaft 38 ts in a bushing 57 provided in the central flange of the member 35a (FIG.

There are a pair of guide bars 61 ('FIGS. .14 and 16) provided on the web or central ange of the swing frame member 35a to properly locate the member 35a between the slot plates I51 and 53.

As shown in FIG. 14, the slot plates 51 and 53 are of generally rectangular form and each is formed with a reverse curve slot 65 in which the pivot shaft 38 rides from an inner position when the swing frame 35 is horizontal, as shown in FIG. 17 through intermediate positions to a position just short of the outer end of the slot when the spring frame is vertical (FIG. 14). The swing frame can move slightly beyond vertical, as shown in FIG. 17, wherein the pin 38 reaches the end of the slot. This overbending is desirable in order that the upright bent plate portion 39a', when released and springs back slightly, will be 90 relative to the central portion 39a" of the plate structure.

As the swing frame 65 is rlirst elevated, it pivots about its inward position but as the pressure builds up between the swing frame 35 and the mandrel 41, a point is reached at which the shaft 38 is forced to move outwardly in the reverse curve slot 65 so that the frame 35 has a wiping compressive action against the plate structure 39 around the mandrel -41 to form a curve (without irregularities) at the corner formed between the vertical and horizontal portions of the frame structure 39. Were it not for this reverse curve slot, the corner 39 would not be true and this would make it impractical, if not impossible, to weld together two adjacent sections of a barge as is' necessary to form the barge B in FIG. 8.

|Referring to FIG. 9, the mandrel 41 s supported at either side of the base frame 31 by the clamp 45, which comprises a pair of half-sections 45a and 45b pivoted at 81 on a standard '83 which is rigidly connected to the base frame 311. A connector 85 connects the clamp halfsections together around the mandrel 41 in the operative position of the mandrel. `Outwardly of the clamps, the mandrel may be equipped with a loop or eye or other means enabling it to be lifted by a crane or other piece of equipment.

The mandrel 41 is of larger diameter than mandrel 43 because it is assumed that ythe larger curve formed by the mandrel will be at the bottom of the barge, while the smaller curve formed by the mandrel 43 will be at the top (as shown in FIG. 5).

There is a clamp 47 at either side of the base frame 31 to support the mandrel `43. This clamp may comprise a standard 91 (FIG. 9) secured to the base frame 31 and having a curved recess at its upper portion to receive the mandrel 43. A movable clamp member 93 is pivoted at '95 on the standard 91, and a locking pin or equivalent means 97 holds the movable clamp member 93 in its operative latching position whereby to hold the mandrel down in relation to the plate structure 3-9.

From FIG. -9 it is evident that the regular spacing of the reinforcing angle strips 40 is interrupted at the location of the mandrels 41 and 43. These angle strips are simply left off until after the curves are bent and they are subsequently welded in place.

In order to retain the structure in place against the swing frames 35 and 37 during elevation of the frames, a pair of angle clip members 101 (FIG. l) is provided for swing frame 35, and a similar pair of angle clip members 103 is provided for swing frame 37. These are simply bolted in place to the swing frames, after the plate structure 39 has been placed in position, and can be removed after the temporary reinforcement or permanent reinforcement has been installed in the bent plate structure.

In order to retain the swing frames in their erect positions, one or more braces 107 and 109 are provided for each swing frame. Preferably these braces are pivotally connected to the base frame, and detachably bolted to the swing frame only after the swing frames are erected. It is pointed out that after the swing frames are swung over center, as it were, in FIG. 17, to put a permanent bend in the plate structure, the swing frame will be moved back to its 90 position as shown in FIG. 4 prior to welding the reinforcement 49 in place.

In addition to the movable clips 1011 and 103, removable side clips (not shown) can also be provided for squaring up the plate structure 39 on the swing frames and holding the plate squarely .in position on the swing frames during the bending process. These clips are likewise temporarily attached in position, and are removed prior to swinging the frames 35 and 37 downwardly, after the reinforcement 49 has been welded in place, or after the temporary reinforcements have been welded in place, depending on the procedure adopted in building a hull half-section.

FIG. 18 shows a modified form of the invention wherein the truss unit 49A is prefabricated as a unit. The plate bending jig of FIG. 1 is utilized to form two L- shaped singly reinforced plate structures 39A and 39B. An unbent fiat deck section 39C with single reinforcement is provided. These three pieces are then welded to the truss unit 49A and joined to themselves by seam welds at their adjacent edges to form a barge section.

In FIG. 19, another modified procedure is shown wherein there is again an unbent deck section 39C, but this time there is an unbent singly reinforced bottom structure 39D. The jig apparatus shown in the drawings and previously described is utilized then to form two C- shaped or channel-shaped singly reinforced plate structures 39E and 39F. The plate structures 39C through F are then welded to the preformed and prefabricated truss unit 49A and to one another at their adjacent edges to form a hull section.

FIG. shows a jig apparatus for forming a U-shaped plate structure, wherein each of the end portions of the plate structure is doubly reinforced, that is, not only reinforced transversely by the strips 39b but reinforced longitudinally by the beams 49Y. In this arrangement, no swing frames are employed, so that only base 31 and the mandrel assemblies are required.

A crane is utilized to lift the doubly reinforced lefthand portion of the frame structure 39 upwardy to bend it around the mandrel 41 and thereafter the right-hand doubly reinforced frame structure is elevated to bend it around the mandrel 43. In other words, in the FIG. 20 form of the invention, the lifting force is applied directly to the plate structure to be bent rather than to a swing frame which in turn bends the structure. After the two doubly reinforced structures are bent upwardly to 90 positions, one or more tie members 123 are welded in place, after which the mandrels are withdrawn axially and further and more permanent reinforcement is applied to the thus formed half-section.

Another similarly formed half-section will be then joined to the section shown in FIG. 21 to form a section of a barge.

In connection with the arrangement shown in FIGS. 20 and 21, it should be pointed out that I have discovered that the curvature produced by this method varies from one bending operation to the next and this variation is undesirable. Thus, while it is feasible to bend plate structures by the arrangement shown in FIGS. 20 and 21, it would thereafter require further work in adapting adjacent sections to one another so that the curvatures roughly match. To the contrary, when the plate structures are bent by the swing frame method, the curves produced are accurate and two adjacent sections mate with one another readily without any or much further work or difficulty. Therefore it is obvious that the FIGS. 20 and 21 form of the invention may be considered as a secondary and less preferable way of bending plate structures as compared with the swing frame method.

Having described the invention in what is considered to be the preferred embodiment thereof, it is desired that it be understood that the invention is not to be limited other than by the provisions of the following claims.

I claim: 1. The method of fabricating a section of a vessel comprising providing a rectangular plate structure which includes a rectangular plate which is reinforced at least in a direction transversely of the plate,

holding down the central portion of said plate structure by the use of a mandrel held against said plate,

raising one end of portion of said plate structure by applying pressure generally uniformly against the underside of said one end portion to bend said plate about said mandrel,

raising the other end portion of said plate structure about a second mandrel to bend it relative to said central portion whereby to form a U-shaped bent plate structure,

similarly forming a second and similar U-shaped bent plate structure,

and arranging said two bent plate structures with certain of their free end edges adjacent one another and Welding together said certain edges so as to form a tubular vessel section.

2. A method as set forth in claim 1, wherein trussing is Welded to the interior of each plate structure prior to the plate structures being joined to one another.

3. A method as set forth in claim 1, wherein said bent plate structures are welded to a preformed unitary truss structure.

4. The method of fabricating a section of a vessel comprising providing a rectangular plate structure which includes a rectangular plate which is reinforced at least in a direction transversely of the plate,

holding down the central portion of said plate structure by the use of a mandrel held against said plate,

raising one end portion of said plate structure by applying pressure generally uniformly against the underside of said one end portion to bend said plate structure about said mandrel,

raising the other end portion of said plate structure about a second mandrel to bend it relative to said central portion whereby to form a U-shaped bent plate structure,

similarly forming a second and similar U-shaped bent plate structure,

and arranging said two bent plate structures in facing relationship and welding the same to a preformed truss unit.

5. A method as set forth in claim 4, wherein flat singly reinforced plate structures are Welded to said truss unit, one between one pair of free end edges of the bent plate structures and the other between the other pair of free end edges of such structures.

6. The method of fabricating a section of a vessel cornprising providing a rectangular plate structure which includes a rectangular plate which is reinforced at least in a direction transversely of the plate,

holding down one portion of said plate structure by the use of a mandrel held against said plate,

raising another portion of said plate structure by applying pressure generally uniformly against the under side of said another portion to bend said plate about said mandrel and thereby provide a bent plate structure of right angular form,

forming a second similar plate structure,

welding said right angular plate structures to a truss unit to form the sides and bottom of a vessel section, and

welding a at plate structure to the truss unit to form a portion of the deck of the vessel.

References Cited UNITED STATES PATENTS JOHN F. CAMPBELL, Primary Examiner R. B. LAZARUS, Assistant Examiner U.S. Cl. XR. 

